Thorne Island

Thorne Island is a small rocky islet, covering around two acres, off the coast of Angle in Pembrokeshire, Wales, dominated by a Victorian coastal artillery fort built in the mid-nineteenth century to help defend the approaches to Milford Haven Waterway and its naval anchorage.

The fort was one of a chain of “Palmerston Forts” built around the Milford Haven estuary in response to fears of French invasion, and its commanding position at the mouth of the waterway made it a key part of the defences guarding access to the former Royal Dockyard at Pembroke Dock. The waters around Thorne Island have a history of shipwrecks, including a notable nineteenth-century wreck said to have been carrying a cargo of Scotch whisky, which reportedly caused a stir among nearby residents.

In the twentieth century the fort was converted for civilian use, at times operating as a hotel, taking advantage of its dramatic, isolated setting overlooking the waterway. Today Thorne Island’s fortress remains a striking landmark for boats navigating the entrance to Milford Haven, one of Wales’s most important natural harbours.

Chough, Puffin and Grey Seal are among the wildlife species recorded in the surrounding area. Search Isle classes it as a tidal island, reachable on foot at low tide. It is one of the islands recorded in the Milford Haven area.